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I wrote a blog a little while ago entitled “One Form of Lift” which talked about the generation of lift and how there was, from an engineering standpoint, no such thing as “impact lift”. Classical engineering analysis only uses lift (which is primarily generated by pressure flows around the wing) and drag. My assertion is that most or all of the force people are calling “impact lift” is really drag, but was there a way to prove it by using a real world example? To take a look at that, I decided to analyze what happens if I stick a set of flat plate wings on my light sport aircraft, a Flight Design CTSW.

We will assume that the wings on the CTSW are mounted so that they are at zero degrees angle of attack (and angle of incidence) when the airplane is sitting level. The wing area of a CTSW is 107.4 square feet and the airplane’s max gross weight is 1320 pounds.

This would get my CTSW with a flat plate wing off the ground at 72 knots while nibbling at the stall. Let’s say you understand this will be the case and elect to back off on the liftoff a bit, flying off at approximately 8 degrees angle of attack. (I believe you will either strike the tail of the CTSW at 12 degrees or be very much at risk of it.) So, when would you want to rotate? At that 8 degrees, you have a lift coefficient of 0.6. That gives you:

2640/.153238 = V2

17,228.1 = V2

131.25 =V (fps) or 77 knots

Since the CT actually gets airborne as low as 42 knots with flaps and about 50 without, you get an idea of the work a good airfoil design (using Bernoulli’s) is doing for you. You can “reverse engineer” the lift coefficient at those speeds by substituting them in for V and solving for CL.

Doing so for the no flap configuration and 50 knots yields a CL = 1.45; in other words, the shaping of the airfoil increases the “flat plate” lift coefficient by slightly over 100%. (The use of flaps yields a lift coefficient of 2.06…which is part of the reason why it leaps off the runway and feels like you’re in an elevator going straight up…)

But, let’s go back to flying by the flat plate alone since our real target is to examine the idea of “impact lift”. As I said in an earlier blog, the only way to do this from an engineering standpoint is to use drag as the “impact lift” force. There is no accounting for such a thing in conventional performance analysis (which should tell you something in and of itself about the rigor of the idea, despite some folks trying to discount how engineers do it).

Let’s see how we might be able to generate enough “impact lift” (drag) to fly. A flat plate has a drag coefficient of 1.28. Since the equations for lift and drag are the same and we’re considering the same area in both equation sets (i.e., only the area of the wings), then we can shortcut the calculation of the total drag force the wings can generate by simply taking a ratio of 1.28/0.7 = 1.83. Then, that same 1320 lbs of total force…now as drag instead of lift…would be generated at 72/1.83 = 39 knots. But this would be for a CTSW wing deflected at 90 degrees to the windstream (and the fuselage). Since we’re just trying to use “impact lift” (i.e., drag) to get airborne, the max lift would occur at a wing inclined 45 degrees to the windstream. The “lift” would be equal to the sine of 45 degrees times the total force. The sine of 45 degrees is 0.707. So, then the speed at which you’d have just enough drag acting vertically to lift off would be: 39 knots/0.707 = 56 knots.

However, for this to occur, the drag acting in the horizontal direction would also be 1320 lbs (sine and cosine of 45 degrees…the horizontal and vertical force components would be the same). Let’s see if the Rotax 912 can get there.

Using Thrust = (HP*efficiency*326)/KTAS and assuming we have a 0.8 propeller efficiency:

1320 = (100*.8*326)/KTS

1320 KTS = 26,080

KTS = 19.75

This is the speed the Rotax could attain in this “lift/drag” configuration. This is a conservative answer since the airplane will have more drag area than this, i.e., we did not account for the frontal area of the fuselage or other components. This puts us well short of the approximate 56 knots it would take to get airborne. To see how big an engine it would take, let’s use the same formula and solve for HP.

1320= (HP*.8*326) / (56)

1320 = (260.8HP)/ (56)

1320*56 = 260.8 HP

73920 = 260.8 HP

283.4 = HP

So, it would take an engine producing almost three times the horsepower the CT has available which would increase the weight and cause us to do all these calculations over again. Keep in mind, too, that we are only talking about the power it would take to get the CT into the air since climb rate is a function of excess horsepower. The engine would have to be bigger still. (At least a 300HP IO-540…) What the numbers are telling you is that the idea of impact lift doesn’t work, and that’s before we try to consider the flying characteristics and design of the flight controls for such a beast. We know that increasing camber (curvature) of an airfoil causes an increase in lift and that’s what makes ailerons and elevators work; how do you explain what’s happening if “impact lift” (drag) is the only force?

“Impact lift” is a misnomer and a popular myth, like saying you can discount Bernoulli’s principles and just use Newton’s laws to easily explain how airfoils work. Good luck with either. From both an engineering and piloting standpoint, it’s better and proper to see lift as a result of Bernoulli’s (i.e., pressure distributions) principles and drag as something that needs to be overcome and is not your friend (except when trying to slow down). You’ll not only stay safer that way but you’ll teach your kids the right concepts, making sure it is “as simple as possible but no simpler”.

AUTHOR’S NOTE: Many thanks to Dave Witwer, Jim Gardner, and Matt Zwack for their review of the drafts of this blog. They’re all pilots and aerospace engineers (Dave, Jim and I worked at Johnson Space Center and Matt works out at Marshall Spaceflight Center.) Great guys I’m honored to know as colleagues and friends!

A week or so ago in an aircraft owner’s forum, the exact thing I was concerned about happened, i.e., a pilot trying to explain how an airplane creates lift to a newer pilot started talking about “the downforce” under the wing that pushes an airplane up into the air (you know, because that’s how the reaction force…referred to in Newton’s Third Law is created…and the airplane reacts by going up!). I’d think it was funny but AOPA’s current iteration of “Essential Aerodynamics” also says that a wing pushes down on the air, creating a misperception that will probably take a decade to clear up. It’s not that Newton’s Laws are not involved; they are. The popular misunderstanding of what that means is fostered by the incorrect idea that somehow only Newton’s laws apply and Bernoulli’s laws are somehow incorrect and is all pure nonsense. So, I’m going to give you a technical explanation of why and do it without going into a lot of math. (I’m going to assume you’re not too dumb to follow what I’m saying, unlike some other folks who say we don’t need to teach aerodynamics like engineers do it because we’re not designing airplanes and then screw the whole thing. If you’re new to this controversy of befuddlement and want to get completely spun up, see the blog entitled “When Simpler Becomes Dumb”, another entitled “Only One Form of Lift”, go through AOPA’s “Essential Aerodynamics” presentation, and come back here. Otherwise, just read on; I’ll explain it in enough detail where you can grasp the core issue.)

The text we used in my aerospace engineering classes discussing aircraft performance was “Airplane Aerodynamics” by Dommasch, Sherby, and Connoly. Section 2:4 “Development of the Bernoulli Equation” explains how,by analyzing a small packet of air as it moves using Newton’s Second Law (F=ma) (Spoiler alert: Newton’s Third Law is not involved here) and assuming no mechanical or thermodynamic losses (conservation of momentum and conservation of energy),one derives Bernoulli’s equation. For incompressible flow (a good assumption for flows less than 200 knots or 230 mph), Bernoulli’s equation is:

p+(D(V2))/2=constant

where p=Pressure, D = air density, and V2=velocity of the airstream squared. P is the “static pressure” term and “D(V2)/2” is the “dynamic pressure” term. So, as the velocity of the airflow increases, the dynamic pressure (pressure in the direction of the airstream flow) increases and the static pressure (pressure of the mass of air and measured perpendicular to the flow) decreases.

Section 4.3 of that text is entitled “Development of the Lift, Drag, and Moment Equation”. It starts out with this: “…the only forces that can act on an object moving through a fluid are those produced by friction (shearing stress in a fluid) or those produced by pressure. Except for when minimum drag is considered, the pressure forces are by far the most important and completely responsible for the production of lift”. (NOTE: I know the reference to “minimum drag” creates a question; I’m researching that and will post an answer here once I have it.) It then goes on to discuss the generation of the force equations associated with deflecting a small packet of air using Newton’s Second Law (F=ma) to calculate the force produced. After showing you the answer, it states: “An airfoil..produces lift by changing the momentum of a given stream tube of air and is capable of producing a force greater than that predicted by the use of simple energy solutions.” In other words, an airfoil produces more force than can be attributed to this simple calculation (F=ma) alone.

So, the blind use of Newton’s second law doesn’t account for the total amount of force generated by an airfoil (or a wing). Notice, too, this analytical approach uses a “microscopic” viewpoint to derive the equations, a common practice when starting at the bottom of an engineering or scientific analysis. How can you figure out what the lift is practically? By stepping back and examining the pressure distributions around the airfoil and calculating the forces they generate. This is easily done, which is why it’s routinely used. (This is using Bernoulli’s principle, folks.)

Have we disregarded Newton’s laws? Not at all! And in doing so, we have generated Bernoulli’s principle, which gives us a more practical and easier to understand approach to working with many aerodynamic problems. Not only does its use make engineering solutions easier, but using Bernoulli’s principle makes for an accurate and easier to understand explanation for the layman. How Newton’s laws apply to aerodynamics is not intuitive; and as we’ve already discussed, often leads to misperceptions, especially when understanding of the subject is incomplete. It’s easy to jump to incorrect conclusions based on what we are familiar with, and most people seem to latch onto Newton’s Third Law, which we see in common thrust/acceleration relationships. Because of that, it jumps into the forefront of thought much more than Newton’s first (i.e., an object at rest tends to stay at rest or continue moving until acted on by an outside force) or second (F=ma).

There’s a more important reason to talk about Bernoulli’s principles when teaching aerodynamics to pilots. When I use Bernoulli’s to explain what’s happening with lift, I not only stick to a technically accurate explanation; but I continue to make a linkage back to airflow around the wing, which for a pilot is the critical thing to control. It’s easy to see the case surrounding controlling the angle of attack to keep from disrupting the airflow controlling the lift. If you try to explain how a wing works using Newton’s Third Law, you will probably think the wing creates a downward jet of air as our wayward pilot did. It does in the form of downwash around a wing but its primary effect on lift is to create induced drag by canting the lift vector rearward and decrease the effective lift the wing produces; to use Newton’s Law second and third laws to find the lift you have to calculate the TOTAL change in momentum of the flow field around the aircraft (and not all of that is going to be in the vertical plane). Want to teach that in your pilot information classes? Better be ready for calculus and lots and lots of work!) If you have a pilot thinking he can create more lift by increasing the wing’s “upward” reaction, you also just created the potential for having a pilot INCREASE back pressure when he encounters a stall to increase the downward force of the “jet” or create “impact lift” (if you teach that concept, too). Poo-poo that possibility if you want; but you can never predict how someone with the wrong idea will react or when you plant the wrong information on their head. I believe it’s a very bad idea to teach anything that is technically incorrect or that can be easily misconstrued into a bad result.

So, the next time you hear that only Newton’s laws apply to aerodynamics and Bernoulli’s don’t, hopefully you’ll understand there’s no way that can be true. Explain that Bernoulli’s equations COME FROM an analysis of the behavior of an airstream using Newton’s laws (Newton’s second, mainly), and you CAN’T DISCOUNT ONE WITHOUT DISCOUNTING THE OTHER. In fact, trying to make the case that “only” Newton’s laws apply can only be correctly understood by PERFORMING a very in depth technical analysis as I have discussed; and that makes understanding the subject harder, not easier. As Einstein said: “Make things as simple as possible. not simpler.”

Guillermo and I manned up the CT the next morning at a little before eight a.m., started her up, and then taxied out to KMDQ’s runway 18. There were very few clouds and the visibility was great as I took us into the skies and turned us west toward Athens, our first checkpoint on Guillermo’s flight plan. I switched us up to the frequency for Huntsville Approach but didn’t check in since we were staying north of the Class C airspace. Ahead of us, a Boeing 737 was climbing out from Huntsville International airport and turning west, climbing up and away. I gave the airplane over to Guillermo at about two thousand as we headed for forty-five hundred. As we did, I spotted another light plane flying toward us at about a thousand feet below; Approach wasn’t talking to him. I puzzled over what type of airplane it was until I recognized it as a T-34 Mentor, one of my favorite airplanes to fly. I had gotten a fair amount of time in them while in Navy flying clubs in San Diego and Corpus Christi, including one flight with my then-wife into Spaceland airport south of Johnson Space Center (JSC) in Houston. I had met an intern working there who sponsored a tour for us which resulted into me flying a forward cockpit Space Shuttle simulator, a precursor to what I would spend a decade doing about eight years later. (Spaceland would later be called “Houston Gulf airport” when I was working at JSC, and I flew out of it for many years before it was sold and turned into a housing development. It was sold shortly after 9/11; it was a private, public-use airport reportedly owned by a brother of Osama Ben Laden (Salem bin Laden) who had been killed in 1988 while flying an ultralight north of San Antonio.)

The T-34 passed well clear below and slightly to our right and underneath while we continued on to our checkpoint and leveled off at our cruising attitude before turning south-southwest. There was a bit of mist in the air that lowered visibilities a little but I still thought we had around ten miles and not a problem. The ride was smooth as we passed over Wheeler Lake and the outlines of Decatur, pointing the nose toward Walker County-Bevill (KJFX) where we had landed on the way up. Guillermo was tracking a bit west of his course line and wasn’t picking up on it until I pointed it out; we corrected as we got close to JFX and then tracked true as we turned slightly more westward toward Downer (You gotta hope the airport is named after somebody and doesn’t reflect the experience there.). We passed under the Meridian East Military Operations Area (MOA); and though it was active, its floor was at 8000 feet so we were well underneath it. Soon, Aliceville, Alabama, the last town we would see before crossing the western Alabama border, was passing beneath us with Downer’s single runway beyond. After I made the customary traffic alerts (i.e., call sign, position, intentions) on 122.8, we crossed over Downer and headed into the flat, green lands of Mississippi, continuing on a southwest line that took us just north of Meridian. We tracked toward Easom (M23), a small airport just southeast of Newton, Mississippi and west of Meridian, while passing within sight of an untowered auxiliary field belonging to Columbus AFB, a towered Navy Outlying Landing Field (NOLF) to our north, and Naval Air Station (NAS) Meridian and Key Field to our south. Pressing on underneath both Meridian 2 East and West MOA’s, we motored on to Prentiss-Jefferson Davis, our last airport/checkpoint before reaching McComb.

Cumulus clouds were staring to dot the horizon ahead, so we knew were moving toward more moist and less stable conditions. There were scattered clouds at our altitude as we approached McComb, and we navigated around them as we pressed toward the airport. I had Guillermo start our descent when the GPS showed we were hitting our descent profile of 500 feet per minute, and the chop picked up a bit as we descended. About ten miles out, I took the airplane back to give myself time to get the airplane set up the way I liked it for downwind to runway 15. We made our approach and landed with fifteen degrees of flap slightly past the first and only turnoff before the end; I braked us to a near stop before making a radio call and back-taxiing on the runway to the FBO.

After our customary break for drinks, bathroom, and fuel, we manned back up and launched out toward Houston with me flying my regular GPS course.
Taking off from KMCB’s Runway 15

The clouds started thickening up, but I still wanted to get above them, so I climbed the CT up to 6500 feet to reach a smoother, cooler ride. But as I got us there, I realized the tops were building rapidly and the bases were slightly descending; that plus a weather report showing broken layers at thirty-three hundred feet over Beaumont made me reverse my plans and head back down. We would make our way underneath to maintain legality under Light Sport rules at 2500 feet.
Making the decision to descend back down.

As we pressed toward the Mississippi river, the air turned a more milky white, the visibilities dropped a bit, and the clouds started closing up the spaces above us.
Approaching the Mississippi River

We spotted some ground fires from what looked like controlled burns we knew were responsible for smoke that was generating the milkiness; the air cleared slightly as we flew across the Mississippi, heading into western Louisiana the NEXRAD weather on the GPS was showing dotted with showers. None of them were on the immediate courseline but some were fairly close, so we decided to watch them for movement and growth but defer any diverts (unless we saw “red” on the NEXRAD) until we could see them out the window. We heard a jet calling as it approached Eunice (4R7) for landing as we were just west passing over St. Landry Parish-Ahart (KOPL) about ten miles away. As we approached Eunice ourselves, we heard the jet’s pilot calling that he was taxiing for takeoff and I responded by announcing we were about to pass over at 2500 feet headed southwest. We watched him taxi out and flew right over him, calling we were overhead and then again when we were a few miles west. He headed south and posed no conflict.
The weather as we approached Lake Charles, LA.

The clouds thinned out as we passed Lake Charles. We monitored the radio for departures out of both Chennault International and Lake Charles Regional, hearing nothing leaving out of the first but there were two out of the second;they seemed to be south of us far enough where we didn’t see them. We continued west, paralleling I-10 toward Beaumont. The lighting of that time of day, our lower altitude, light traffic, and me flying from the right seat let me observe that highway through the city in a way I never had. I saw all the places I knew from my travels along it as I headed to and from Alabama both during family visits and my volunteer work on the Tomcat.

After we passed over Beaumont (KBMT), we turned south-southwest toward Chambers County (T00), our last checkpoint before hitting the Houston area. I made sure I knew where the two thousand foot radio towers were and kept us above them; as we passed over Chambers County, I used the sectional on my iPad to review Houston’s Class B floor configurations to make sure I wouldn’t fly into them while still holding us as high as I dared over Galveston Bay to keep engine out glide capability to its northern shoreline. As we approached the Bay’s northwestern corner, I descended us down to 1700 feet to get under the Class B floor over La Porte and Clear Lake.
Over Chambers County and heading into Galveston Bay

Once we had passed the Kemah restaurant cluster guarding the entrance to Clear Lake, I descended to 1300 feet and turned us west, passing just south of JSC and Webster. Staying south of NASA Road 1 will always keep you out of Ellington’s Class D airspace, so I obeyed that until just east of Polly Ranch and had Pearland in sight. The Pearland ASOS advised us that the winds were favoring runway 14, so I flew us into downwind, slowing to my normal pattern speed of 75 knots, before pulling the throttle back abeam my landing point, dropping the flaps to 15, and then making a successful if a bit firm landing on that runway.
A moment before touch down on Runway 14 at KLVJ

CONCLUSION

Somehow, it all seemed anti-climactic. There’s no way you can tell when whether you had any impact with the kids at all, especially when you live so far away and probably won’t see them again. All you can do is hope you made a positive…and, if you are lucky, inspirational…impact on some kid you talked to who never realized that aviation (or manned spaceflight) could be theirs…that it wasn’t something just for the rich and famous. There are ways to get there even if you don’t grow up in a household of advantage, and I am an example of that, though I was not subject to the additional difficulties that often arise because of one’s race. My family didn’t have the money to support me learning to fly or going to college, and things did not go well for the only other person in my family who tried to go into aviation. Still, I am grateful I had his example so I knew how not to let adversity drag you down all the way when I stumbled into it during my own aviation pursuits. You gotta keep pressing on and make the lemonade you can. I persevered, and while I didn’t get to where I wanted to go I got to places I would not have anticipated and were, in some ways, better for me as a human being. It led to quite a career, one that made me very happy and showed me just how talented I was. Love at its best…

About six weeks or so after Guillermo and I made this trip, Russell Lewey sent me a very nice card that included a note written by one of the students. She thanked me for traveling so far to teach her about airplanes and told me how much it meant to her to see one up close. That single note says that it was worth doing; and I can tell you I would not hesitate to do it again and again, as long as I have the chance. Whether it is her that presses on into aviation or spaceflight or one of her compatriots, I can’t say. I can only hope.

For there was someone who inspired me, though I am not sure he ever realized it. He wasn’t a pilot or an engineer but an Opelika High School social studies teacher named Andrew Lisman. When all my other classmates just thought I was weird, he always seemed eager to stand me up on Current Events day and explain to the class, with my model spacecrafts in hand, what was going on with any ongoing US manned spaceflight mission. It was the heyday of Apollo, so there were several. They were enough to form my only real validation of my love for flight; and to this day I am extremely grateful for it…and to him. Without it, it’s hard to say whether I might have ever pushed forward to chase my dreams; and they are what led me and still lead me to take flight in whatever way I can.

Guillermo and I spent the night in a La Quinta in Madison and met the next morning for its complimentary breakfast before heading out for the FlyQuest shop over at Hunstville International. I was looking forward to meeting Russell Lewey for the first time as we plugged in the destination into the iPhone and started toward the airport. The iPhone GPS decided that the shortest route was one that took us into a cargo gate; we were staring at a TSA shack we knew we weren’t going to get past when we figured it out. I turned us around and headed us toward the main gate to the airport when Russell called, and he confirmed I was now headed the right way and told us how to get there. A few minutes later, we had wound our way past the main terminal and found the FlyQuest shop, which was collocated with a new flight school, Revolution Aviation.

Inside the door, we met Russell and the manager of the flight school, Chris Burns. Russell led us back to the simulator. It is a 6 degree of freedom motion base simulator by Precision Flight. Russell told us they had acquired it as a prototype, even though the company now had them in production. Saying it was ready go, he opened the rear door and we stepped up into the cab. Guillermo went first; he was going to fly left seat as the pilot in command. I dropped into the right seat to find that only the left had the controls; but since the worst that could happen was we could crash the sim, I was okay with it. Russell was at the instructor’s station which was outside the cab; we talked back and forth via headset. We were sitting on the long runway, i.e., the twelve thousand feet of runway 36 Left in a simulated Cessna 172. Since Guillermo had only flown airplanes with a Rotax engine, I talked him through the start up sequence. The engine sprang to life. No takeoff checks necessary; we pushed the throttle forward and the airplane followed. We rotated at about 50 knots, and we were off!

We continued pressing north, climbing to 6500. Once there, we leveled off and then I told Guillermo to hold his altitude and pull the throttle to idle. We got slower, and slower, and slower, creeping up on a stall.

“Keep it going….keep it going!” I urged. “All the way into the stall!”

The stall horn started going off. We felt the airplane shudder.

“Keep the stick back. NOW! FULL LEFT RUDDER!”

The nose dropped, the airplane rolled and whipped to the left, corkscrewing the nose straight down. I noted what the ground looked like and what was directly “up” as we twiseted left and around.

“One…two….three! Neutral stick! Right rudder!”

The airplane came to an abrupt stop, fishtailing a little back and forth as Guillermo figured out how much rudder he needed.

“Look at your airspeed! We’re really FAST; start pulling back on the stick but NOT TOO FAST!”

The nose came up fairly quickly. Guillermo stopped it at the horizon.

“Power back on,” I said. “Take us to cruise!”

“Nice job, “ I continued.

“Let’s do that again!” Guillermo exclaimed.

And we did! Spin after spin, some right, some left; and one that started left, went flat, bobbed, and broke right as Guillermo danced on the rudders, reversing them to see what it would do.

With only a few minutes to go, I broke off the spin training and Russell reset us into the pattern for Cullman, a small airport south of HSV. We made three practice runs, working to get consistent stabilized approaches and, hopefully, a simulated landing. Unfortunately, we didn’t get there; Guillermo had a tendency to hang high so getting to a landing could only be done if one was a Kamikaze. That was something we were going to have to fix in the real world. The hour of time we had paid for was up.

We chatted for a few minutes about the session, confirmed the schedule for the rest of the day, and then left while Russell took a young man back to the simulator. Guillermo went back to our rental car, made our way out of the airport to I-565 East, flying down the highway to Exit 15, the exit to the US Space and Rocket Center. At the top of the exit, I turned right toward the Center and immediately left to take us down to Aviation Challenge. Left turn, right turn, and one hill and down another until the road was intersected by a fence separating us from the sharp, finned form of the F-14 Tomcat standing beyond.

After parking the car, we made our way through the gate at the sidewalk, and I walked Guillermo around my F-14 as he photographed her using his phone.
A picture of the F-14 as she sits at Aviation Challenge.

When I had known the Tomcat in our youth, she had been the Navy’s premiere fighter/interceptor, launching off carrier decks, intercepting real bogies inbound toward the task force as it sailed over the world’s oceans; shooting missiles at drones; rolling in for simulated kills against everything from A-4’s to F-4’s, F-5’s, other F-14’s and even Omani Jaguar’s; and jinking away from simulated missiles. She was quiet now, standing there kneeled for the catapult with her wings swept back, something you’d never really see. She looked in really good shape. Very little dirt covered her paint still shiny from the refresh we had given her a year before. I didn’t think she would look that good. The only thing I noticed untoward was a single bird’s nest stuffed into a wheel well. You had to admire a bird that could pull that off since we had closed up most of the Tomcat’s landing gear doors to try to keep the critters out. It was just another lesson on how resilient and resourceful life really is.

To see the rest of Aviation Challenge, Guillermo and I walked around the building used for classes, simulations, and bunk rooms to the stands, hoists, and aircraft hulls positioned in the water egress training area. I explained the purpose of the the “helo dunker” (a helicopter version of the Dilbert Dunker) and the water slide (parachute harness egress training) before taking him to a nearby F-4 whose history included a MIG kill during the Vietnam War. Next we visited a Navy A-7, an Air Force F-111 and F-16, a Navy Seasprite helicopter, a T-38, and a MIG-17 before making our way back past the F-14, said goodbye, and returned to our car in the parking lot.

After a lunch at Chick-Fil-A, we returned to our hotel for a break and to get ready for the afternoon. I was really looking forward to delivering a presentation on Aircraft Systems to FlyQuest students from Mae Jemison High School. Afterwards, we were going to let the kids go out to the CTSW to see and touch an actual aircraft, though you gotta’ be careful they don’t touch too much…!

For a little “show”, I put on what I call my “Fancy Bag”, a royal blue and Navy blue flight suit styled somewhat like a uniform from Star Trek: The Next Generation. It sports a set of gold NFO wings on the left chest, a Flight Design CTSW patch I designed and had made on the right one, a 1000 Hour Tomcat patch on the left shoulder, and another CTSW-centric patch on the right. I combined that with a black and red “VF-51 Tomcat Project” ball cap whose logo I also designed, and then met Guillermo downstairs in the La Quinta where we were staying before driving back out to Huntsville Executive. When we arrived, Russell was already there with his wife Diane and set up in the airport’s conference room. After we all met each other, Russell and I chatted about how I was going to present; I had brought a MacBook Pro I was going to use if needed but Russell had one ready. I practiced with the pointer/slide controller, making sure I knew how to make my slideshow work as we heard the school bus containing my audience pull up in front of the building.

The kids and their advisers piled out of the bus and into the room, filling it with noise and activity. Russell had mentioned it was an unusual class in that the students were mostly female. They were also mostly African-American and from Mae Jemison High Schoo. Many if not all of its members were from the Air Force Junior Reserve Officers Training Corp (ROTC) there. While I was ex-Navy, I had been in Army JROTC while at Opelika High School few hundred miles south; in addition to an interest in aviation, I had some Alabama high school experiences in common with them.

Russell had a big bag of candy at the top of the table, motivation to keep the young crowd engaged and motivated. I sat down in chairs along the side of the long table that formed the center of the room as the kids filled it in on all sides except for the very front where Russell stood. Russell reminded them what we were her to cover and tossed candy to the students who successfully answered his questions. He introduced me and I moved to the front of the room, told the kids a little bit about myself, and then proceeded into the presentation.

Edward Tufte makes his living talking about how using PowerPoint makes people stupid; and though I had practiced with the material, I quickly learned that when you are talking to kids, that’s close to the truth. A more accurate description of what happens is the kids find it BORING, no matter how enthusiastic the presenter is. And I was. Russell jumped in to rescue me with candy and a Jeopardy game show approach that kept things alive until we had covered the parts of an airplane and what they do. Then, the adult advisors and Russell led the group outside onto the ramp, stressing how important it was to both stay together and pay attention to taxiing airplanes.

Out at the CTSW, we split the kids into two groups with Russell taking one and me the other.
Russell Lewey and his kids at the CTSW.

We opened the aircraft’s doors to let the kids see inside the cockpit, and I started at the nose of the aircraft showing the kids the aircraft systems we had just discussed, going down the aircraft’s left side as Russell and his group started at the tail and went up the right.
Yours truly with my group of kids at the front of the aircraft;

The kids were surprised the airplane was so small and to learn that it had an emergency parachute that lower could it to the ground. Even as small as it was, I pointed out, Guillermo and I could take off from KMDQ and be in Houston only 6 hours later while costing only 30 gallons of gas.

For many of these kids, it was the first time they had been that close to any airplane. One young woman was shocked to discover she didn’t need an academic degree to become a civilian pilot; it just took learning the skills and passing written and flight tests. I could see her wheels turning as she pondered the possibilities she might not have known were there.
One of the students looking into the cockpit of the CTSW.

After a little over a half hour out at the airplane, we gathered as a group just outside the FBO and Russell’s and the teachers took photos of us all. Then, we returned into the building while the kids piled back onto their bus.

I spent a few minutes thanking Russell for rescuing me and discussing how to approach kids in that age group. Russell felt I had done fine, though I wasn’t sure of that since I had seen a kid or two nodding off. Nothing like coming in from out of town and leaving with a reputation intact. I usually put at least twice that many adults asleep….

That evening, Guillermo, Russell, Matt Zwack, and I met at a local restaurant Russell had suggested named “1892 East”. (See http://www.1892east.com.). It was a great little place with good food and ambiance. Matt was a friend of mine, a fellow volunteer on the Tomcat Project as well as a fellow pilot and aerospace engineer, and a colleague in manned space flight. We all listened as Russell shared with us many of his experiences as an Air Force B-52 and instructor pilot. We talked about Flyquest since Matt was coming to talk to the same kids in a few weeks to share his experiences as an aerospace engineer. We were joined briefly by Ed Steward, the Director of Exhibits at USSRC, who couldn’t join us for dinner but take a few minutes to say “hello” and let us talk about the Tomcat as well as the other space related projects I was curious about. For dinner, I had a pan roasted North Carolina stuffed trout, with fingerling potatoes, and broccoli. Nothing like a good dinner to top off the evening talking with good men and fellow pilots. A great way to top off a very satisfying day.

One of my great passions right now is to inspire kids to get involved with aviation and space. I’ve done quite a few Young Eagle flights, and the Experimental Aircraft Association’s dedication to that program is the prime reason I stay a member since I’m not building an airplane and don’t have any immediate plans to do so. I’ve looked into getting involved with other programs in Houston; but, so far, having found anything I could participate in as a Light Sport instructor. As I’ve said before in this blog, the aviation education community is missing opportunities to get and keep kids engaged by not getting them into their Light Sport rating vice soloing them as Private Pilot students and then dropping them off. I’m working on getting an Advanced Ground Instructor (AGI) rating to see what doors it might open; and I’m always looking for more opportunities to engage youth with aviation and space in some way. Sadly, the opportunities in Houston seem a bit limited, even though it’s Space City.

For about a two-year period, I was the volunteer leader of a team restoring a F-14A on display at the US Space and Rocket Center in Huntsville, Alabama. I was shuffling from my Rocket City to the other in the CTSW, flying into Huntsville Executive Airport because of their great hospitality and absence of landing fees. The particular F-14 we were working on had been in my fighter squadron, the Screaming Eagles of VF-51, and I had flown in her 28 times as a Radar Intercept Officer (26 times in VF-51 and twice in VF-124), mostly while we were on an “around-the-world cruise” aboard the USS Carl Vinson in 1983. While I was in Huntsville on one of my trips, I learned about FlyQuest, an educational non-profit whose goal was to bring kids into the aviation fold and enhance STEM (Science, technology, and math) education. They conducted programs that engaged homeschoolers, middle school, and high schoolers and sponsored or participated in local events. I don’t remember now how I first heard about the; but, as I looked into them, I thought that what they were doing was the best thing since sliced bread, and I wanted in. My first attempt to engage with them was during a Women In Aviation event; one of the volunteers on the Tomcat team, Clarissa, and I planned to attend to encourage anyone interested to join us on the Tomcat team. I printed up brochures and flyers and Clarissa made a large and wonderful photo collage. I planned to fly the CTSW up not only as personal transportation but to throw in with a Young Eagle rally being conducted by EAA Chapter 190 in conjunction with the event. Unfortunately, snow and ice clobbered the runway at KMDQ on day before the event when I needed to fly in; and despite several conversations with the FBO on the phone, I couldn’t get any solid estimates for when the runway would be usable. Runways at KHSV were in use, but there were still NOTAMS about ice on the taxiways. Staring at those conditions, I just couldn’t see committing to that trip in the CT and the prospect of a 13 hour drive solo one way wasn’t attractive either, so I backed out.

I tried later to meet up with them at an AOPA fly-in up in Tennessee; but weather once again became an issue and I couldn’t figure out a good plan to work around it. I didn’t see an opportunity to get engaged with them again until the summer of 2016 when they asked for volunteers to teach classes in an aviation summer camp. I signed up to teach a class in aerodynamics and was really looking forward to it, especially after discovering some issues with material they had borrowed from a Rod Machado text that I wanted to correct (See my blog about “Only One Form of Lift”). But, sometimes, life has its own plans; my mother-in-law’s health started rapidly deteriorating and my wife was diagnosed with a life-threatening form of bladder cancer, and I wound up with more important priorities. A few months later, I learned they were going to hold some afternoon high school classes and inquired about teaching the aerodynamics class, but the aero class was taken and the classes that were open required me to move a doctor’s appointment that was ridiculously hard to get. I figured I was done. But Providence stepped in. A few weeks before that class, the doctor’s office called and asked me to reschedule; so, after checking with my wife about whether she was okay with the trip (and getting a “yes”), I immediately contacted FlyQuest’s Educational Director, Russell Lewey, and asked if there were still classes open and could I come up? He was happy to oblige. He had an aircraft systems class open that was being taught at KMDQ; and, if I flew up in the CTSW, the kids could go out and see the systems we were teaching them about. I signed up with glee! Now, all I needed was for the Gods of Weather to cooperate, as fickle as they are.

As the time approached, the Gods smiled, and it was looking like a flight in the CTSW was going to be possible. Connie would not be going with me, so I had an open seat in CT and a Light Sport student whose dream was and is to make the long cross-country from Houston to South Carolina. I invited him to accompany me. Guillermo was thrilled to go, so I told him to pick two legs of the four leg trip to flight plan and fly using only the Sectional (How archaic!); we would fly the other two legs using GPS and routes I already had put together. The overall plan would be to fly from Pearland (KLVJ) to McComb, Mississippi (KMCB) and from there to Huntsville Executive (KMDQ), about a six hour flight, and then return home using reverse legs a few days later.

Guillermo is an architect who does very detailed planning for a living, and his flight planning reflected it. I had never seen such details fleshed out of a flight plan since training in the Navy for low level missions. He did a very thorough, detailed job; but there were still some details to tweak and it would be difficult to sustain his approach once he was on the road. He had included reproductions of the sectionals cut and assembled into a booklet, great for handling in the cockpit but taking lots of printing and construction time, something you were not going to have sitting in an FBO and replanning your next leg due to weather. Additionally, he had used some Class D airfields as checkpoints, no sweat as long as you know you can fly over the top of them but something never guaranteed due to Light Sport rules (no overflight of a cloud layer that cuts off contact with the ground). I prefer to form plans that don’t have a high probability of being forced to change on the fly; so I pointed out to him that he would have to deviate or get permission to go through if the ceiling was lower than the top of the Class D. He moved his checkpoints to accommodate those comments, and I deemed us ready to go.

On the Tuesday morning of September 20th, we manned up under clear but hazy skies. The weather brief had said we’d have 10 miles visibility, but the haze and blazing morning sun cut effective visibility down to about half that once we were in the air. The winds were out of the east and would get higher the closer to Alabama we got, but we had something less than a ten knot headwind when we took off and headed east. I performed the takeoff on runway 14, climbed us out toward the southeast, then east, and leveled us off at 1500 feet AGL. I gave the airplane to Guillermo. Flying his flight plan, he cut us across Galveston Bay; and once we moved from under the 2000 foot floor to the 4000 foot Class B floor, he climbed us up to 3500 feet and leveled us off, heading us northeast toward Beaumont. Since were dependent on the sectional for navigation, I pressed Guillermo frequently to show me where we were, and he did an admirable job of putting us right where we needed to be and was always on top of it. His preflight prep really paid off.

ATIS broadcasts for Beaumont were still calling it clear; but as we pressed to the north of it while traveling east, I noticed an thickening band of clouds ahead at our altitude. It was a layer of cumulus clouds with bases right where we were and tops two thousand feet higher. While they weren’t impossible to get over, their coverage was going to make it difficult to wind our way through them, and I wasn’t ready to try to climb over them until I understood conditions beyond. The Lake Charles ATIS was also calling “clear”; but we could see clouds down to the coast and continuing east, and there were much larger build ups over the Gulf to our south. I pulled in the latest report for McComb using XM Satellite weather on our GPS display; it was saying the airport was clear with at least six miles viz. METARS only give you the conditions at the airport and only hint at what might be beyond, but I still felt there was a good chance what we were seeing would not last. It was a safer bet to go low, so I told Guillermo to drop down to three thousand and fly there.
The view at 3000 with Guillermo flying to McComb

The clouds plagued us until we were passing Lafayette and then cleared out as I had hoped. The rest of the flight to McComb was in the clear with almost no clouds at all and only light chop that increased a bit as we approached the airport. Guillermo performed the descent to the forty-five degree entry for left traffic on runway 33; I took over a couple of miles from the airport and flew the downwind to a landing.
The McComb Mississippi(KMCB)FBO

After fueling up and taking a bathroom and snack break, we manned up and departed northeast. Optimal winds were still a thirty-five hundred, so I leveled us there and then let the autopilot fly the GPS course. Guillermo was content to rest and look around.
“Otto” Flying toward KMCB.

However, as we approached Alabama, the turbulence began to increase until I couldn’t stand the dives and climbs the autopilot was doing and I took over for the rest of the trip. The closer we got to Huntsville, the more headwinds and turbulence increased. I was throttled up to handle the headwinds; and, at about an hour out of Huntsville near Jefferson County, I was having trouble telling visually how much fuel we had left. While I knew by fuel burn and time we probably had enough to get there without landing (and that when you’re bouncing around, fuel can appear to hide in the wings), I decided to land at Walker County to check it out. (Frankly, I get curious about airports I often fly over and my curiosity makes me want to land just to check them out.) I aborted the flight as we flew past Waklker County airport, teardropping into a left downwind for runway 9, and then performing a flaps up landing with the windsock standing out to the right as I taxied over to the fuel pumps to shut down. Once the airplane was stopped, not rocking, and level on thee ground, I could see we did have the fuel to get there with some reserve; but it only made sense to add some more fuel to increase our margin. We did, got back in, and taxied back out.

I let myself get faked out on the takeoff. I taxied out to 9 again as the ASOS was reporting calm and a limp windsock confirmed it. We did our takeoff checks and, since the winds seemed to have died down, I dropped the flaps to 15 and started the takeoff roll, rotating at a calm wind speed of 42 knots. As soon as the nosewheel came off the ground, the airplane started hard drifting right; I countered with more left rudder and got us airborne inputting a hard left crab as we passed the windsock standing out to the right again. Lesson learned. With the flaps down at 15 and the nose in the air, the airplane’s ability to counter drift ain’t very good; keep it on the ground until a slightly higher speed and then pop her off like I know to do.
What a Flubbed Crosswind Takeoff at Walker County Looks Like!

After bouncing through the air for about another twenty minutes, I called Huntsville approach about 25 miles out. They surprised me by clearing me direct to KMDQ at 3500 feet. From where we were, that would mean a direct overflight of Huntsville International just slightly offset from the US Space and Rocket Center and its full-scale Saturn V mock-up. Acknowledging the call, I turned us on heading as the turbulence started kicking us for all it was worth. I slowed us down to Va (98 knots) to keep my airplane in one piece. Once, the airplane dropped so violently we were sure the earth had to have moved; without seatbelts, we would have smashed our heads into the ceiling.
What it Looks Like When The Earth Moves While Flying

Holding on, we continued toward Huntsville Executive as I edged the course a few degrees west to make sure I didn’t knick a restricted area. I assumed it was “cold” since approach had said nothing to us, but I figured there was no reason to test it out.

We already had Huntsville Executive in sight. The winds were out of the north meaning a landing on runway three-six. We had a very gusty ten knots of crosswind as I aligned us with the runway centerline and visually picked up the VASI (Visual Approach Slope Indicator). I left the flaps up due to both the magnitude of the crosswind and its gustiness and came in a bit too fast, trying to get her settled down as we crossed the threshold. Trying too hard to get a smooth touchdown, I bobbled the airplane in pitch; on the third bobble, I had hit my personal safety criteria (three tries to get down), eaten up more runway than desired, so I cobbed the throttle to go around. I saw the linemen, who had come out on the ramp to show me where to park, throw their hands up in frustration as they heard the engine gun and saw me go. Nothing like the roar of the crowd..! And they weren’t even serving peanuts…

I flew a right downwind for three-six, making sure I got a good setup abeam, and then flew a right base and final to complete the landing with a solid thump. That was good enough. I taxied us down and off the runway and over to the parking spot where the linemen were waiting with our rental car, happy just to be where we needed to be safe and sound.
The CTSW shut down and empty at KMDQ. The FBO building can be seen out the right window.

From the author: I apologize for the delay and the disjointedness of posting this. I’ve been dealing with a family medical issue and thought I still needed to write the second half, knew it would take a while, had the AOPA issue jump up which I thought was quicker to deal with, and then realized this part was done and I just needed to post it.

There was sign next to the self-serve fuel pump I hadn’t seen before. It mentioned a “SUPERUNICOM” operating on the same frequency as the Common Traffic Advisory Frequency (CTAF), 122.8 for this airport. I had never seen or heard of it and, since I was focusing on getting the CT refueled, I didn’t take the time to read it. I fueled up for the next leg, and then met Connie inside the FBO. We sat down to a lunch of peanut butter crackers and Diet Coke while I pulled out the iPad and plotted a new course for our next leg.

Our next fueling stop was to be in Mount Pleasant, Texas. It’s an airfield we typically use as a fuel stop on the trip to Missouri and back from Houston. A single but very nice six thousand foot runway, great facilities, great people, and airplanes from the Commemorative Air Force. To get to it down the west side of the mountains, we still needed just a small jog further west, so I planned to fly southwest to Grove near Lake of the Cherokees before turning almost due south toward Texas.

The winds were strongly out of the southwest when we taxied out for takeoff on runway 19. Three clicks on the CTAF frequency (and not by us) triggered off an automated voice telling us the wind direction and velocity, our SUPERUNICOM at work. Once we were ready, I gunned her up the hill for 19 using no flaps because of the strong, gusty crosswinds, and we hit the top of the gradient about the same time I got to flying speed. We got airborne with a little hop before starting to climb away and turning right almost immediately. I climbed around the scattered clouds at speed driven again more by the oil temperature gauge than anything else. We leveled off a forty-five hundred feet for this leg; the winds were better there, the clouds were below us, and the ride was fairly smooth. To our left, the deck looked fairly solid, the cumulonimbus clouds were still there and quite tall, and I was very glad I had made the decision I did. As we flew over the ridgelines to the south we would have to cross, the clouds looked like they were lower than I had initially thought.

As we motored south past Sallisaw and Fort Smith under the clouds to our east, we saw a regional airliner cross several miles in front of us in a descending left turn. We watched him arc toward the cloud deck and then disappear beneath it as we moved toward skies that were turning milky. The visibility was dropping below us. At first, I thought it was mist; but there was a whiteness to it I couldn’t reconcile. As the puffy clouds moved past us below, one of them was as black as the side of a heavy thunderstorm, even though it was only a hundred feet tall and wide. Then, we were suddenly flying over a wildfire, the source of the white smoke that was filling the sky. There was no one or any equipment down there; it was burning in a solid east-west line. We pressed on south beyond it, and the sky quickly began to clear.

Soon, we were swinging past the snake-like curves of the Red River and entering our home state of Texas. We were still about thirty minutes away from Mount Pleasant, three hours flying time away from home, and a six to seven-hour drive if we were to switch to a car. It was just before two p.m. in the afternoon, the sun was blazing, and the clouds were building, fired up by moisture from the Gulf of Mexico still hundreds of miles away. The visibility was good but not unlimited; there seemed to be some haze in the distance. The cloud bases were moving up but they were also growing vertically; I knew there was a good chance that the next leg of the trip south toward Houston would have to be flown lower, both because of a slight change in heading and because of the building clouds. Both the NEXRAD satellite weather being displayed on our Garmin 496 and the view out the window said there were building cumulonimbus clouds just east of our route; once I got on the ground at Mount Pleasant, I’d take some time to recheck forecasts and take a more leisurely look at them for development and movement. With the long day, we could wait out any convective activity if needed; there was often a two to three hour window late in the day after the thunderstorms had died down when you could fly in, and that was just enough time to get to Houston from there. Since we were flying Light Sport rules, we would have to turn into a pumpkin shortly after sunset; if we couldn’t touch down at Pearland by then, Mount Pleasant would be our stop for the night.

We started picking up KOSA’s AWOS; winds were light and out of the south-southwest, meaning we would be heading for a straight in on runway 17. As we approached, I heard a Bonanza also coming in from the west; but he was much closer so I expected him to be on the ground by the time we got there. I slowly descended the airplane down to about two thousand feet AGL, and we bounced toward the city of Mount Pleasant which we could see through the haze. The confines of the airport and then the black strip of its runway slowly materialized, and I let down to the pattern altitude of 1400 feet to pick up the red and white lights of the 4 light PAPI. They were all white, so I pulled the power back and started slowing down to eighty knots so I could drop to fifteen degree flaps. There was just a little bit of gustiness in the winds, so I slowed down to sixty knots instead of a calm wind fifty-four and flew the glide slope on the PAPI using power until I made the runway and I touched her down.

Turning right onto taxiway Charlie, I called clear of the runway over the radio and headed us toward the FBO and the self-serve gas pumps to the north side. Pulling up to the pump, I went through the Shutdown checklist, pinning the BRS to keep it from being inadvertently fired, shutting down my electronics and then the engine before pulling the circuit breakers that act as a Master switch. We opened the doors and slid out, and Connie headed toward the FBO while I got out and headed to the pumps to get us gassed up before taking my break.

Unlike the day before when a low pressure system in the Gulf had pumped lines of thunderstorms up from the south, the cells I was seeing on the radar seemed to be moving very little and the coverage was isolated to small pockets we could fly around if needed. The forecasts were calling for a chance of thunderstorms until six p.m., but our route (for the moment) was clear. As Connie and I took another Coke and Cracker break, I told her it looked good for pressing on. We had the option of stopping for the night at Nacodoches if Houston got socked in; there was bed and breakfast there I was interested in checking out if the need arose. So, after getting refreshed and briefed, we climbed back into the CT and took off to the south.

The cloud bases were at about forty-five but the tops were up at about eight thousand and rising in the fiery sun, so I leveled off at thirty-five where it was about eighty degrees and infected with a bumpy ride. Turbulence usually forces me to hand fly the airplane especially with Connie aboard; I do a better job smoothing out the bumps than my simple autopilot which has no filters and climbs and dives like a Kamikaze in them. We flew south past Longview, Nacodoches, and Lufkin before driving just east of the large Class B ring surrounding Houston, watching the rain from numerous cells fall in misty sheets just east of us. I held our altitude until we were approaching the east side of Galveston Bay, before letting down to 2500 and finally 1500 feet to scoot under the floors of Houston’s Class B. Hugging the coastline on the north to give us some option other than ditching if we suffered an engine out, we made our way past La Porte and the restaurants at Kemah before turning west just south of Clear Lake. The familiar haunts of Johnson Space Center and Webster slid down our right side; we could see the large expanse of runways that are Ellington Field just beyond. I dialed in Pearland airport’s ASOS; the winds were favoring runway 14. We entered the pattern on a forty-five from the southeast, put the flaps down at fifteen on the downwind abeam, and landed, glad to be home.

I’ve always loved to teach. That love has led me to multiple places within the realm of aviation and aerospace, starting with being the nerdy kid standing in front of his high school government class with his models of Gemini and Apollo spacecraft, to being a NATOPS instructor in the F-14, an astronaut trainer at NASA’s Johnson Space Center for a decade, and a Light Sport Flight Instructor and blogger (writer) today. Through it all, I’ve always strived to make difficult technical subjects accurate and understandable to my audiences.

I’ve also seen and experienced the other end of the scale, i.e., instructors who made technical content more complex that it needed to be in an apparent scheme to demonstrate their mental superiority to students, and instructors who “simplified” the material to the point it became technically inaccurate. Both approaches are a form of arrogance or ignorance; take your pick.

I’m a personal fan of Einstein’s admonition that “everything should be as simple as it can be, but no simpler”. About two weeks ago, I was in Edward Tufte’s class on presenting technical data where he stated that “dumbing down is pandering”. How true! The assumption behind any “dumbing down” is that the audience is not smart enough to understand the technical material but the presenters are. This is often not the case. As a good friend of mine used to say: “You can’t give away what you don’t have”; and that applies to the understanding of a subject as well as other things.

The latest unfortunate example of something dumbed down to the point of being technically incorrect is the current iteration of AOPA’s “Essential Aerodynamics” presentation. Frankly, there is nothing essential at all about it; I do, in fact, steer my students away from it. You know something is dreadfully wrong with their approach when they state that the “wing pushes down on the air”, something that simply does not happen. I say that as an aerospace engineer who, as a student, plotted the pressure distributions about a subsonic wing section in a wind tunnel. Once you see the large low pressure area above the wing which grossly outclasses the high pressure areas underneath, you can intuitively tell that the most accurate explanation for what is happening is that the wing is sucked up from above.

So where did AOPA get the idea that the wing pushes down on the air? I don’t know, but it could have been from someone taught by a teacher who bought into a poorly thought out push by the American Association of Physics Teachers (AAPT) in the early 2000’s to replace Bernoulli’s law, which does a good job explaining how a wing generates lift, with Newton’s laws. The best rebuke to that approach was written and published in their magazine, “The Physics Teacher, Volume 40 in 2002 by aerodynamicist Charles N. Eastlake and entitled “An Aerodynamicist’s View of Lift, Bernoulli, and Newton”. (Ask Google to find it.) In it, he explains how both sets of principles apply and then goes through a technical explanation of the airfoil and how lift is created. He emphasizes that the choice of which set of use depends on which one is simpler to use. Indeed, we did use both approaches (i.e., Bernoulli’s and Newton’s) in various aerodynamic problems to find the answers. But since most kids and many pilots are not going to know how to use calculus, I personally believe that using Bernoulli’s explanation is not only correct but intuitively easier to understand. Additionally, you can use it in a classroom with very simple models (i.e., wing sections and simple wind tunnels) and do the calculations to show the forces involved, something that is difficult to do when using Newton’s laws to calculate the change in momentum of the airflow. When you talk to most people about Newton’s laws, and especially about Newton’s third, they intuitively understand it when talking about the application of thrust, since that’s what we’re nearly all familiar with. But start trying to relate that to the change in momentum of the total airflow field (the Newtonian approach), and they’ll scratch their heads or come up with some off-the-wall and technically incorrect explanation that the wing on a fixed wing aircraft pushes down on the air. Using Newton is a more intuitively easier approach to use and understand when talking about how propellers, jet engines, or rotor blades create force (thrust or lift), even though Bernoulli’s principle is alive and well and at work in them, too.

The AOPA presentation also decides that explaining aerodynamics using a wing is too hard, so they use a surfboard generating “lift” as it races through the water as their example. This is truly baffling, since it ignores one of the major rules of communication (common symbols and experiences between the transmitter and receiver) and totally fails to account for the force of buoyancy, which airplanes other than seaplanes don’t have for long if they land in the water. There simply was no reason for it; it did nothing to simplify the explanations of relative wind or angle of attack and brought the confusing environment of the water in the picture. (Daddy, how come an airplane doesn’t float in the air? My surfboard does.)

The presentation excuses its approach by telling viewers they don’t need to use the common approaches used for a century to explain aerodynamics because they were used for designing airplanes and it only needs to educate pilots (i.e., pilots are not smart enough to understand it). I didn’t think anything of that at first, until I saw where they were going. After that, I felt it was a red flag that it was all about to go off the track. True enough, pilots don’t need to know how to use calculus and integrals or the power and drag required values to calculate what to do next. But they do need to have a proper understanding of how a wing works and that needs to tie intuitively with what’s going on in the cockpit. I can use Bernoulli’s and angle of attack to make it clear what a stall is and that reducing the angle of attack to break the stall is all that counts; I’m not even sure how you could approach it when trying to explain it using Newton’s laws using change of momentum. In fact, I could easily see how someone not grasping it might think you need to use the wing to throw more air at the ground and pull the stick back HARDER. (The same action can result by teaching someone to believe in “impact lift”, which is not lift at all but drag acting in a vertical or near vertical direction.)

I did contact AOPA about this and forwarded them a copy of Eastlake’s article. In response, I got some mealy mouthed excuses about the difficulty of presenting complex technical material. The lesson has remained unchanged. Additionally, a few months after I set my response, “Flight Training” magazine, when promoting this presentation asked its readers “Newton or Bernoulli?”, stepping into the same nonsensical environment the AAPT had created. It’s not an either or choice, except when you’re trying to explain it. To do that correctly, you need to know what you’re talking about. And better care.

There’s a reason why NASA websites and the FAA’s “Handbook of Aeronautical Knowledge” uses Bernoulli for their basic explanation of aerodynamics. Too bad you don’t get WINGS credit for going there; you should.

There was sign next to the self-serve fuel pump I hadn’t seen before. It mentioned a “SUPERUNICOM” operating on the same frequency as the Common Traffic Advisory Frequency (CTAF), 122.8 for this airport. I had never seen or heard of it and, since I was focusing on getting the CT refueled, I didn’t take the time to read it. I fueled up for the next leg, and then met Connie inside the FBO. We sat down to a lunch of peanut butter crackers and Diet Coke while I pulled out the iPad and plotted a new course for our next leg.

Our next fueling stop was to be in Mount Pleasant, Texas. It’s an airfield we typically use as a fuel stop on the trip to Missouri and back from Houston. A single but very nice six thousand foot runway, great facilities, great people, and airplanes from the Commemorative Air Force. To get to it down the west side of the mountains, we still needed just a small jog further west, so I planned to fly southwest to Grove near Lake of the Cherokees before turning almost due south toward Texas.

The winds were strongly out of the southwest when we taxied out for takeoff on runway 19. Three clicks on the CTAF frequency (and not by us) triggered off an automated voice telling us the wind direction and velocity, our SUPERUNICOM at work. Once we were ready, I gunned her up the hill for 19 using no flaps because of the strong, gusty crosswinds, and we hit the top of the gradient about the same time I got to flying speed. We got airborne with a little hop before starting to climb away and turning right almost immediately. I climbed around the scattered clouds at speed driven again more by the oil temperature gauge than anything else. We leveled off a forty-five hundred feet for this leg; the winds were better there, the clouds were below us, and the ride was fairly smooth. To our left, the deck looked fairly solid, the cumulonimbus clouds were still there and quite tall, and I was very glad I had made the decision I did. As we flew over the ridgelines to the south we would have to cross, the clouds looked like they were lower than I had initially thought.

As we motored south past Sallisaw and Fort Smith under the clouds to our east, we saw a regional airliner cross several miles in front of us in a descending left turn. We watched him arc toward the cloud deck and then disappear beneath it as we moved toward skies that were turning milky. The visibility was dropping below us. At first, I thought it was mist; but there was a whiteness to it I couldn’t reconcile. As the puffy clouds moved past us below, one of them was as black as the side of a heavy thunderstorm, even though it was only a hundred feet tall and wide. Then, we were suddenly flying over a wildfire, the source of the white smoke that was filling the sky. There was no one or any equipment down there; it was burning in a solid east-west line. We pressed on south beyond it, and the sky quickly began to clear.

Soon, we were swinging past the snake-like curves of the Red River and entering our home state of Texas. We were still about thirty minutes away from Mount Pleasant, three hours flying time away from home, and a six to seven-hour drive if we were to switch to a car. It was just before two p.m. in the afternoon, the sun was blazing, and the clouds were building, fired up by moisture from the Gulf of Mexico still hundreds of miles away. The visibility was good but not unlimited; there seemed to be some haze in the distance. The cloud bases were moving up but they were also growing vertically; I knew there was a good chance that the next leg of the trip south toward Houston would have to be flown lower, both because of a slight change in heading and because of the building clouds. Both the NEXRAD satellite weather being displayed on our Garmin 496 and the view out the window said there were building cumulonimbus clouds just east of our route; once I got on the ground at Mount Pleasant, I’d take some time to recheck forecasts and take a more leisurely look at them for development and movement. With the long day, we could wait out any convective activity if needed; there was often a two to three hour window late in the day after the thunderstorms had died down when you could fly in, and that was just enough time to get to Houston from there. Since we were flying Light Sport rules, we would have to turn into a pumpkin shortly after sunset; if we couldn’t touch down at Pearland by then, Mount Pleasant would be our stop for the night.

We started picking up KOSA’s AWOS; winds were light and out of the south-southwest, meaning we would be heading for a straight in on runway 17. As we approached, I heard a Bonanza also coming in from the west; but he was much closer so I expected him to be on the ground by the time we got there. I slowly descended the airplane down to about two thousand feet AGL, and we bounced toward the city of Mount Pleasant which we could see through the haze. The confines of the airport and then the black strip of its runway slowly materialized, and I let down to the pattern altitude of 1400 feet to pick up the red and white lights of the 4 light PAPI. They were all white, so I pulled the power back and started slowing down to eighty knots so I could drop to fifteen degree flaps. There was just a little bit of gustiness in the winds, so I slowed down to sixty knots instead of a calm wind fifty-four and flew the glide slope on the PAPI using power until I made the runway and I touched her down.

Turning right onto taxiway Charlie, I called clear of the runway over the radio and headed us toward the FBO and the self-serve gas pumps to the north side. Pulling up to the pump, I went through the Shutdown checklist, pinning the BRS to keep it from being inadvertently fired, shutting down my electronics and then the engine before pulling the circuit breakers that act as a Master switch. We opened the doors and slid out, and Connie headed toward the FBO while I got out and headed to the pumps to get us gassed up before taking my break.

Conclusion

Unlike the day before when a low pressure system in the Gulf had pumped lines of thunderstorms up from the south, the cells I was seeing on the radar today seemed to be moving very little and the coverage was isolated to small pockets we could fly around if needed. The forecasts were calling for a chance of thunderstorms until six p.m., but our route (for the moment) was clear. As Connie and I took another Coke and Cracker break, I told her it looked good for pressing on. We had the option of stopping for the night at Nacodoches if Houston got socked in; there was bed and breakfast there I was interested in checking out if the need arose. So, after getting refreshed and briefed, we climbed back into the CT and taook off to the south.

The cloud bases were at about forty-five but the tops were up at about eight thousand and rising in the fiery sun, so I leveled off at thirty-five where it was about eighty degrees and infected with a bumpy ride. Turbulence usually forces me to hand fly the airplane especially with Connie aboard; I do a better job smoothing out the bumps than my simple autopilot which has no filters and climbs and dives like a Kamikaze in them. We flew south past Longview, Nacodoches, and Lufkin before driving just east of the large Class B ring surrounding Houston, watching the rain from numerous cells fall in misty sheets just east of us. I held our altitude until we were approaching the east side of Galveston Bay, before letting down to 2500 and finally 1500 feet to scoot under the floors of Houston’s Class B. Hugging the coastline on the north to give us some option other than ditching if we suffered an engine out, we made our way past La Porte and the restaurants at Kemah before turning west just south of Clear Lake. The familiar haunts of Johnson Space Center and Webster slid down our right side; we could see the large expanse of runways that are Ellington Field just beyond. I dialed in Pearland airport’s ASOS; the winds were favoring runway 14. We entered the pattern on a forty-five from the southeast, put the flaps down at fifteen on the downwind abeam, and landed, glad to be home.

It’s been a tough summer for us. Connie, my wife, discovered she had a serious medical condition and, in the middle of us dealing with that, her mother, who had been suffering from failing health, died. Her dad, a Marine World war II veteran and 95 years old, was still adjusting to the loss of his only partner (as we all were), and Connie felt she both wanted and needed to spend some more time with him. The thought of driving that trip was too much for me; so we decided to fly the CTSW up over Labor Day weekend, when I had an extra day off. The weather for the trip looked pretty good for the trip up from Houston and it was; while it was too rough a ride for Connie down low, the bases of the scattered cumulus clouds were around five thousand, so I took us to 6500 feet where we found light headwinds and a smooth ride. We flew from Houston to Mt Pleasant, Texas (one of the most hospitable airports anywhere; I left my billfold there once and the airport manager flew it down to Conroe where I retrieved it with nothing lost.), and then on to Rogers at Bentonville Arkansas and finally to Kirksville, Missouri where we bedded the airplane down. We had originally scheduled our return for Labor Day; but we had known when we left that the weather might be problematic for a return. I got up early and started checking weather. The Terminal forecasts for Houston hobby were talking about thunderstorm activity but Convective SIGMET issuances were expected. The National Weather Service forecasts were talking about a system in the Gulf pumping bands of moisture up from the south…. thunderstorms and locally heavy rain were possible with the chance of rain was about 60%. It was still forecasted to be VFR outside the TRW activity, but when you see those kinds of rain chances in Houston you have to be concerned about whether you can work your way around even with a VFR forecast. The storms often move in bands south to north; and, if you’re coming down from the north, you’ll be forced to make her large deviations or divert to avoid them. I was certain from the forecasts we could get to Mount Pleasant before we ran into anything and maybe Nacogdoches if we were lucky, but I told Connie the odds were good we would have to spend the night north of Houston and scoot in the next morning. She didn’t want to “stage” an arrival; and, since our whole point in making the trip was to give her the most time possible with her dad, I made the decision to delay a day when the forecasts looked better.

“Better” does not mean perfect. No matter which day we went home, winds were going to be a big issue through Missouri. On the surface they were out of the south to southwest at sixteen gusting to 24, forecasted to be one knot below the recommended operating limit on the surface for the CT. (I had operated the CT in winds up to about 22 kt gusts, and the airplane buffeted around on the ground but was very manageable at zero or negative six flap settings.) Crosswinds were not going to be a big problem, but headwinds were and I was concerned turbulence might be. At three thousand, winds were forecasted to be out of the southwest at thirty knots plus, which would take a big chunk out of the CT’s 112 knot no-wind cruise speed. The winds actually got better as you went higher; forecasted winds at 6500 were down to 25 knots or so. That made the big question: could we get there or would the cloud decks force us below? Sometimes, the Gods of Class E airspace and Light Sport rules would force you to descend because the cumulus clouds would be building so high it was not possible or practical to go over them. So, down you’d go to maintain adequate ground contact…even with a perfectly functioning moving map GPS…into a turbulent ride. All we could do was get going and see where it led.

We took off from Kirksville’s runway one eight at about eight-thirty in the morning. The winds were blowing almost straight down the runway at ten knots, so we got off fast and were climbing right away into wind getting higher fast. By the time I was climbing through three thousand feet, the GPS groundspeed was showing only 25 knots, a number I had never seen before on my GPS even when playing with slow flight in a headwind. (Best rate…which I was climbing at…was 78.) I kept her climbing, using a cruise climb set more by my engine oil temperature than anything on the airspeed indicator. We slowly made our way up to 6500 feet, where I nosed her over, popped the flaps into their minus six degree, full-up position, and let the engine accelerate us to cruise. Our ground speed clocked up to 87 knots, exactly the 25 knot headwind component we were expecting. Thankfully, the ride was smooth, so I clicked on the autopilot and let it track the course in our GPS while I followed our progress on my iPad, tracking my emergency landing fields as we flew past them. Even when we were out of range of any, we were still in good shape; below; the green farm fields were flat and separated by crisscrossing, long dirt and paved roads, any of which would do to land the small CT on if her engine croaked.

We steered southwest, turning south just to the west of the huge expanse that was Whiteman AFB some ten miles or so away. We picked up some knots with the turn; our groundspeed climbing up to 93 knots. We were now running a few knots ahead of the flight plan, making me feel a little better about not having any problems getting there. Until I used XM satellite weather to pull down the latest METAR. Our destination was the Class D airfield at Rogers, Arkansas, the home of the Walmart FBO. The METAR reported the field was broken at 2700 feet, eight hundred feet lower than the forecast had predicted. While that was plenty for us to get in, it was below the three thousand feet I use for flight through that area. Rogers is at the north end of a mountain bowl full of airfields that included North Arkansas Regional, Springdale, Fayetteville, and Fort Smith. To get out, we had to cross a ridgeline south of Fort Smith that jutted up to 2700 feet MSL, leaving us 1400 feet to go over it. While that was workable, it was not desirable, and the winds over it would more than likely make it a jolting ride.

As we approached Monnet, Misssouri, I could see the broken layer ahead, an ever thickening lake of cumulus clouds only three or four hundred feet thick. It went as far south as I could see, completely covering the mountains I knew we were approaching. What really got my attention was a cluster of towering cumulonimbus clouds slightly off to the east, signaling to me that possible rain and even thunderstorm development that could happen here could be an issue. I was very concerned that the ceiling and developing weather could keep us trapped in the valley for the afternoon, delaying us to the point of not making it to Houston today. I started looking at the iPad, which had our current position displayed on a sectional, for possible divert fields. Joplin was the closest and had the best facilities, but I wanted something both further south and east to reduce fuel consumption on the next leg and give us some room to scoot down the mountain range on the east side. I checked the information for Neosho; it was in a better location and had a city run FBO with self-service 100 low lead. At that exact moment, my wife, seeing the same things out the window that was concerning me, said something about a divert. Disengaging the autopilot, I pointed the airplane at Neosho and told her we were headed there, rather than heading into an area where I had doubts that we could proceed on when we wanted.

We tracked past Joplin and as we approached Neosho, I throttled back a bit to begin a descent. The ride roughened considerably as we descended past Granby, angling toward Neosho and the single north/south runway of its airport beyond. I dropped us down to about two thousand feet, scooting beneath the dotted clouds, as I angled us right to align with the runway for a very long straight-in. Connie spotted an aircraft on our right side and low; it took me a minute to find it, thought it was a twin at first but realized it was a crop duster as I got a better look. He seemed to be slowly angling away from us even further right; I saw him turn across a highway and seemingly head toward a field I assumed he was going to work, so I told Connie to keep him in sight and let me know if he headed our way. I continued toward the runway looking for other traffic and making a couple of radio calls marking our position and our intentions, when Connie let me know he had turned and was headed toward the same runway we were. I picked him up and, sure enough, he seemed to be flying a lot faster and was bee-lining toward the approach end of the runway, seeming oblivious to our presence and the radio calls I was making.

We were approaching runway one-nine with a lot of turbulence and a gusty, ten knot crosswind. The crop duster was about a half mile in front of us, touching down on a slanted runway that looked like it was running up a cliff before folding over and running flat, hiding its far end. Connie thought we needed to wave it off, that the crop duster was going to turn around and back taxi, but I told her I was continuing, confident there was a turn off at the end of the runway if not before. The airplane did turn off before getting to the end, just as I touched down a little past the first third of the runway and about half way up the climbing hill.

We turned left just north of the FBO, taxiing toward the gas pump we could see and past the crop duster and its pilot, who was exiting the airplane. I shut the CT’s engine down, and we opened the airplane’s gull wing doors to the hot air the gusty wind was circulating.